[unreadable] Research advances over the last several years have provided overwhelming evidence that the health of humans, and likely most other animals, is dependent upon their associations with persistent, coevolved communities of microorganisms. Not only do these consortia of beneficial microbes play a critical role in day-to-day physiological homeostasis, but also they partner with the host's immune system to resist pathogenesis. This latter role has taken on an increasing significance in an age of emerging infectious diseases and sophisticated bioweapons development. Investigation of the normal microbiota and its interactions with the host has been enabled by recent technical advances in molecular biology and biotechnology, including the development of methods to identify the constituents of microbial consortia, to define their behavior, and to determine the depth of their influence on host biology. The ASM Beneficial Microbes conferences, in 2005 and now 2008, are internationally attended meetings that bring together biologists in areas ranging from molecular genetics to systems biology and ecology to discuss the development of this frontier field of research. Funding is requested for the support of United States and international scientists attending the upcoming meeting entitled 'Beneficial Microbes Conference 2008 - Host- Microbe Interactions in Health and Disease', sponsored by the American Society for Microbiology (ASM), and to be held in San Diego, California, October 12-17, 2008. The meeting has six sessions devoted to exploring the current state of the field and defining new directions of inquiry. The first session focuses on the description of host- associated consortia, i.e., our current knowledge of microbial species-composition and function in these communities. Then, because all animals, including humans, are products of evolutionary selection, we follow with a second set of presentations exploring the ecological factors and pressures that drive and maintain genetic diversity in these consortia. The third session investigates how microbial associations influence host physiology, and describes the biochemical mechanisms underlying the interactions. Because the immune system is the major element in an animal's response to the presence of microbes, the next two sessions are devoted to exploring the role of the microbiota in normal immune function, and the recognition signals that allow communication between a host and its specific symbiotic partners. The last session looks to the future, introducing novel models for the study of beneficial animal- microbe interactions, as well as a fostering discussion of new frontiers, such as the biology of beneficial viruses. Recent research has demonstrated that humans require interactions with thousands of coevolved microbial species for health, and that the activity of these microbes is likely to profoundly affect all aspects of human physiology and immunology. The recognition of this phenomenon is revolutionizing the way biologists and biomedical scientists view the form and function of the human body. 'Beneficial Microbes Conference 2008 - Host- Microbe Interactions in Health and Disease' is an American Society for Microbiology- sponsored meeting devoted to exploring this frontier. The aim of this conference is to provide a forum for discussion and exchange of ideas, and for the development of new approaches and a conceptual synthesis. [unreadable] [unreadable] [unreadable]